HTTPS Everwyhere:
Copyright © 2010-2012 Mike Perry <mikeperry@fscked.org>
Peter Eckersley <pde@eff.org>
and many others
(Licensed GPL v2+)

Incorporating code from NoScript,
Copyright © 2004-2007 Giorgio Maone <g.maone@informaction.com>
Licensed GPL v2+

Incorporating code from Convergence
Copyright © Moxie Marlinspike
Licensed GPL v3+

Net License: GPL v3+ (complete tree)
GPL v2+ (if Moxie's NSS.js is absent)